Lake Berryessa is the largest lake in Napa County, California approximately 20,000 acres. There are many activities for the explorer and local alike. Several marinas provide watersport activities and can help facilitate your adventures on the lake. Boating, swimming, hunting and camping. There is plenty of activities to do at Lake Berryessa. Whatever you and your family likes to do you will find plenty to do here at Lake Berryessa!